In an approach to detection of potential merge errors when merging source code, a computer detects a source code merge process start. The computer compares at least one change made to a main stream of source code to a child stream. The computer determines whether one or more of the at least one change made to the main stream are not included in the child stream. Responsive to determining one or more of the at least one change made to the main stream are not included in the child stream, the computer determines the one or more of the at least one change made to the main stream that are not included in the child stream were removed from the child stream during a software development activity. The computer flags one or more files of the child stream corresponding to the one or more of the at least one change.